In 2003 Daniels, Blumberg et al. proposed to combine ground and aerial experiments to identify buried objects. Here, we inquire about next steps that could be taken to push forward the research for subsurface 3-D mapping in particular by utilizing satellite data. They analyse the dependence of the total returned electrical field, and quoting Campbell et al., they argue that “SAR systems using long wavelength can complement an orbital sounding system and ground penetrating radar in order to obtain an optimal depth penetration, vertical resolution and volumetric local data”. In view of this objective, we work on SAR Remote Sensing theoretical models, to show how we could reach a relatively fine (few meters) depth resolution for subsurface mapping, in particular in very dry lands or in ice regions. Those opto-geometrical models aim to measure the change of Doppler shift as a function of the relative antenna-target velocity and the look angles, using multiple antennas, orbit revisits, or several measures at various stages of the flight with only one antenna, and in turn, infer the height or depth of a target (or layer). Two main outcomes of our study are the determination of an optimal look angle for topography and the definition of a horizontal upper limit of a groundwater table. Our ultimate goal is to map the subsurface for various geomorphological layers, with maximum penetration in the ground and the best possible resolution. This study is relevant for climate change, desert agriculture and development and natural resources management.

4. Mr. Daniel Kamoun
Remote Sensing Techniques for Groundwater Measurements in Drylands Subsurface
Brandeis University, USA